Motherboard Short

Doc11354

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Hello. I believe I somhow shorted my new motherboard. I am putting together a low budget PC. The spec.s are as follows
MSI P35 Neo motherboard
Cheapie case (no brand name)
Power Rebel RB-ATX 400A power supply ( installed later a Kentech PSPK 600 watt power supply)
Intel P4 2.8 Ghz 775 LGA processor (going to Intel C2D 2.33 ghz processor)
3 gig Elpida pc6400 ram
Segate 80 gig SATA HD
DVD rom drive
XFX Radeon 4350 Pci-E video card
1 80mm case fan.
The problem is: I assembled this and it was working fine except the Bios hardware monitor showed the CPU temp at 64C while at idle. Knowing this to be an extremly high
reading, I took out the cpu fan and processor and cleaned both with Iso. al., reapplied new Artic Silver paste and reassembled both. The processor is seated properly in the socket and the mounting pins on the cpu fan are completly thru the motherboard. I received a 120mm case fan and installed it in the front of my case. This required removing the front of the case. When I tried to restart the machine, the fans, both case fans and cpu fan. will come on. The system will run like this for approx. 5 seconds then shut down. It will then try to restart after about 3 seconds and go thru the same process. I removed the 120mm case fan thinking this might be too much for this small power supply. While doing this I discovered that the front audio connector had bare wires. I taped these wires and can confirm that they are not touching any bare metal. Now all the system will do is the loop of trying to boot. It does NOT stay on long enough to get to the bios screen. I believe this has shorted the motherboard somehow. I did take all componets out of the case to bench test it. I omly had the motherboard, 1 stick of ram, the video card and the power supply connected. When I plugged in the power supply the system tried to boot. I did not have to short the pins on the motherboard for the power to be applied. Is my motherboard now TOAST??? I do not have another motherboard to test this, although I have purchased a used one from E-Bay ( will be arriving approx. 9/16/2011). Any help would be appreciated. Thank You
 
1) Verify that you have the front panel led pins connected properly. If you have inadvertantly connected one to the reset pins, you will get the symptoms you describe.

2) Take the motherboard out of the case and connect only the minimal components and see if it will boot.
 

Doc11354

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Gofelt
1 I installed the front panel leads according to the motherboard manual. They are correct.
2 I have already bench tested this outside of the case, with minimal componets, CPU, Cpu fan, 1 stick of memory, video card (tried 2 different video cards. 1 Pci-e and 1 pci) and power supply connected to the 24 pin main connector and the 12V cpu connector and still get the same results.
Any other ideas????
 
If the motherboard tries to boot without shorting the pwr leads, then I think the motherboard is likely shot.
Check carefully to see if there could be some sort of short in and around the front panel pins.

At this point, though, I would not throw good money at the pc to try and fix things.
It is several generations obsolete, and even the cheapest sandy bridge replacement will be much better.

 

Doc11354

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Thankyou. I believe you are correct. I have done some more checking on the motherboard. There does not appear to be any burnt spots. I followed the circuit using a magnifying glass and didn't see anything. I have read some other posts and tried to do some checking the way they did. I found out that if I unplug the 12V cpu connection the machine will come on, Cpu fan running and the processor getting hot to the touch. I set the cpu fan to the side just to see if the processor was actually getting any power. It was. I only did this for a second to touch the top of the processor. While the power was ON, cpu fan runing, when I plugged in the 12V 4 pin connector the machine immediately went into shutdown and then restart. This tells me the motherboard is shot.
Thank you for your help.